U.S. Publication No. 2013/0106437 (“the '437 publication”) discloses a monitor for monitoring isolation resistance, impedance, or other isolation reflective conditions between vehicle systems. The monitor may be useful in assessing an insulation resistance between a high-voltage power net and a low-voltage power net. The monitor may be configured to assess a sufficiency of the insulation resistance based on a frequency response of the high-voltage power net.